andrewschuh

I've been running carefully over threads about how to replace a head gasket on my 88 4runner (22re). I have tried to be ultra careful but at the last second, my focus became entirely on the setting the headgasket and dropping the head correctly. I then torqued up the bolts w/o spinning the camshaft so that the dowel was facing directly up (noon). So now I'm left w/ the dowel at about 8:00 instead of 12:00, while my sprocket hole is still lined up at 12:00. Is there any remedy for this? Possibly spinning the crankshaft and lining them up at 8:00, putting them on, then spinning it back to 12:00? Or do I have to pull the head, replace the head gasket and spin it right before torquing down?

Obviously I'm a newbie, I appreciate any advice anybody can give.

Kiroshu

It might be just me but your post is kind of confusing. IF your doing a head gasket job its best to get the engine to top dead center before taking things apart. Assuming you got the crank to its proper postion along with the head i'm not sure what your problem is? It sounds like you didn't line up the cam and or it moved and its off? How far off did it go and which way? If it only moved a few teeth either way just turn it back it should be fine.

Crank sprocket dot at 6:00

Cam sprocket dot at 12:00

^ do that and you should have no issues.

andrewschuh

Sorry, again, first time in engine so I'm a bit over my head. In the Haynes manual, it says on 2A-8, 12-5, position the camshaft with the dowel pin at the top (12:00 position). This is presumably because the camshaft will turn freely before the head bolts are torqued down? I did put everything to TDC (I guess so the chain and sprocket are good) but the head went out to the machine shop and came back (I assume) with the camshaft dowel positioned at 8:00 instead of 12:00. I somehow hopped over this step after placing the head, not realizing that I might have to spin the camshaft to get this dowel aligned BEFORE torquing down the head bolts. Does that make sense?

Kiroshu

So you tourqed the head down with the cam at 8:00?

Kiroshu

>_<...

Kiroshu

Loosen the head up and rotate the cam to 12:00.

andrewschuh

do i jeopardize the integrity of the head gasket this way? It took me a long time to get everything out of there and likely a bit of time to get everything put back together. If there might be any problems, I'd rather just get another head gasket and do it the right way considering the time I've already put into it. What do you think?

Kiroshu

Just try not to pick up the head and the gasket on there should be fine. Just loosen the rocker assembly and turn the cam to 12sih then re-tourqe. Make sure you loosen the head in the proper sequence and tighten.

andrewschuh

...weighing options. When you don't know much, (and don't have the time) you tend to do things "safe". I'm assuming somebody out there might tell me that I should replace the head gasket now. $48 more at Toyota sucks but being confident of my job might make it worth it I guess. I really don't want to do it again any time soon.

c0ugar69

just loosen the adjusters for the valves all the way and then rotate the cam back then when all done adjust the valves.

c0ugar69

no need to loosen the head

SoCal4Running

Correct me if I wrong here but cant you just move the crank a quarter turn?

At TDC the #1 and 4 pistons are at maximum height and the 2 and 3 are at the bottom. Turn the crank 90 degrees and all 4 are in the middle of the block and then just line up the cam where it should be for chain installation and then bring the engine back to TDC.

There may already be valve damage done from installing the head but just do a compression check before assembling the rest of the efi and stuff and this will let you know.

The pistons cant get any higher no matter which way you turn the crank.

andrewschuh

Although I'm not sure what I'm doing, my idea was along the lines of SoCal4Running. Seems like I should be able to turn the crankshaft a quarter turn, align everything, then turn it back to TDC carrying the camshaft w/ it. I hadn't really thought about potential valve damage, which would suck. How would I go about a compression check w/o anything but the head/block in there?

SoCal4Running

I am thinking about NOT having the chain on at all. Move the crank by hand and then move the cam to where it needs to be, then bring the crank back to TDC and then install the chain.

For a compression check, put the chain on and and crank the motor. No intake, no exhaust. You will need to disable the fuel pump but I'm sure there is a fuse you could pull or something else someone on here would know about.

You could just jump the solenoid contacts with a screw driver with the ignition off, the only thing that matters is the starter has to turn the motor over. The key does not need to be on.

c0ugar69

that sounds like a even better way moving the crank abit, didnt think of that..owell always learning something new.. good luck I think it will be ok, but i like to think positive!!!

andrewschuh

so, "chain doesn't need to be on"? Mine is just zip-tied and marked and resting (on the tensioner or whatever is beneath it ). So, I should just turn the crankshaft as is, align the camshaft dowel w/ the sprocket and slip the sprocket on ... but then the chain is moving when the crankshaft turns so it wouldn't seem to matter whether the chain is on the sprocket or not when it is turned back to TDC? right? it is the combination of the crankshaft and sprocket which will turn the camshaft back to noon?

SoCal4Running

Oh yea forgot about the chain being on the crank already. whoops!

Gonna have to cut the the zip ties and rotate it while keeping tension on it. Then re zip tie it so you can rotate the cam, then cut zip ties again and rotate back, re zip tie again and install sprocket onto cam.

I doubt you could rotate the crank and chain to the perfect position to get it installed where the cam is now.

Maybe just loosening the valves is the best way.

andrewschuh

well, what I have done so far is rotate the crankshaft which "sort of" rotates the sprocket and chain. The zip tie is near 1 o clock so I can crank a quarter turn and bring it around 9 o clock at which point I can slip on the sprocket and if I want "tighten up the bolt" and then turn the crankshaft a quarter turn clockwise back to near TDC. Would this be bad? or fix my problem?

andrewschuh

Well enough for tonight, my options end up being (1) keep the chain on the sprocket, rotate the crankshaft quarter turn counter clockwise, slip on camshaft and then rotate crankshaft quarter turn clockwise. Whether it is good or bad, I already have the sprocket on in this 8 o clock position so it would be easy. Alternative (2) is to pull it off and reposition to TDC, and loosen valve adjusters I guess to move camshaft. Option (3) might be to remove sprocket, go back to TDC, take head off and have it checked out by somebody for valve damage and then install w/ a new head gasket the right way. ... I'm tired.

Lextech

Are there any lobes pushing on valves at 8 o clock? I have never seen anyone install a head with a load on the valves and I'm not sure if it's even possible? I think it would be quite noticeable while setting it down and torqueing. I'm thinking the valves would just push on the pistons and move the crank position a bit, unless the spark plugs were in? Just unbolt the cam sprocket, slide it off, rotate the cam and crank individually, and while you are doing it if there is any excessive resistance you'll know...Put them where they need to go and reinstall the cam sprocket. The cam sprocket takes just a bit of prying to get it back on the sprocket. Remove the spark plugs if you haven't already and it'll be that much easier.